Dyfyniad APA

(2003). Precaution, envirnmental science, and preventive public policy. Washington: Island Press.

Dyfyniad Arddull Chicago

Precaution, Envirnmental Science, and Preventive Public Policy. Washington: Island Press, 2003.

Dyfyniad MLA

Precaution, Envirnmental Science, and Preventive Public Policy. Washington: Island Press, 2003.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.